简介:IntroductionTherecentdiscoveryofaclassofcarboncontainingmoleculesknownasthefulereneshasproducedaseriesofmaterialswithawideran...
简介:Onenewsesquiterpenecompound,namely,illihenlactoneA(1),andonenewprenylatedC6–C3compound,illihenryioneH(2),alongwiththreeknownsesquiterpenes(3–5)wereisolatedfromthestemsofIlliciumhenryi.Thestructuresof1and2wereelucidatedbyspectroscopicevidenceincludingNMR,HRESIMSandcirculardichroism(CD).Compound2exhibitedaweakinhibitoryratioforbglucuronidasereleaseinducedbyplatelet-activatingfactor(PAF)inratpolymorphonuclearleukocytes(PMNs)invitro.
简介:Thispaperreportstwolanthanidecomplexesofformula(C9H7)Ln(C8H8)·(THF)2whereLnisProrNd,C9H7isindenyl,andC8H8iscyclooctatetraene(COT).ThecomplexeswerepreparedbythereactionofLnCl3withK(C9H7)andK2(C8H8)inTHF.(C9H7)Pr(C8H8)·(THF)2crystallizesinTHFat-15℃inthemonoclinicspacegroupP21:withunitcelldimensionsa=8.446(0),b=10.083(2),c=13.407(3),β=105.48(1)°,V=1100.43(35)3,Dc=1.52g/cm3andZ=2.ThefinalRvalueis0.033,Rwvalueis0.030,respectively.In(C9H7)Pr(C8H8)·(THF)2afive-memberedringcentroidofC9H7,theC8H8ringcentroidandthetwooxygenatomsfromthetwoTHFmoleculesformadistortedtetrahedralgeometryaroundthemetal.
简介:C19-DITERPENOIDALKALOIDSOFDELPHINIUMMOLLIPILUM¥SuoMingZHANG;QingYuOu(LanzhouInstituteofChemicalPhysics,ChineseAcademyofSci?..
简介:TheinteractionbetweenC60’sinsolidC60hasbeencalculatedby(exp-6-1)potential,andthecauseandthecontrolledfactorofthehighrapidrotationsofC60’swerediscussed.InordertodescribethedisordereddegreeofC60rotation,anequivalentMisintroduced.Thephasetransitionsatthe~260Kandatthe~90KarestudiedfromtheviewpointofC60rotation.Thepotentialbarriersoftheorderedrotationbelowthe~260Kandthedisorderedrotationabovethe~260Khavebeengiven,andtheeffectoftheexternalpressureonthetemperatureofphasetransitionhasalsobeengiven.
简介:Animidazolemodifiedsilverelectrodeispreparedbyimmersingthesubstratesilverelectrodeina2%imidazolesolutionofethanolat50℃for10min.Themodifiedelectrodeisthensweptinacytochromecsolutionandthemodifiedlayertakesoffbecausethemodifiedelectrodeisveryunstable.Althoughtheamountofthesilver-imidazolecomplexisverysmallcomparedwiththeamountofcytochromecintheproteinsolution,itgreatlyfacilitatesredoxreactionsinvolvingthebiomacromolecules.
简介:TheconstructionofadsorptivetypeC60modifiedelectrodeanditselectrochemicalreductionandoxidationbehaviorinaqueoussolutionsaredescribedinthisreport.Fourpairsofone-electrontransferreductionandoxidationcyclicvoltammetryisobtainedinaqueoussolutioncontaining30%CH3CNand2%(C2H5)4NOH.ItisreportedinthispaperthattheC60modifiedelectrodealsocatalyzestheelectrochemicalreductionofdissolvedoxygenin40%DMFand2%(C2H5)4NOHaqueoussolutionandthismightopenanewfieldforthepotentialapplicationsofC60inelectrochemistryandelectroaualyticalchemistry.
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简介:CarbonsupportedPt(Pt/C)electrocatalystswerepreparedwithglucoseasprotectionagentandNaBH4asreductant.ThePtnanoparticlesdepositedoncarbonsupportpresentedreducedsizeandwelldispersityattributedtotheprotectioneffectofglucose.GlucoseabsorbedontheparticlesurfacewasreadilyremovedbywaterwashingwithoutleadingtoagglomerationofthePtnanoparticles.Theas-preparedPt/Celectrocatalystsshowedimprovedmassactivityformethanolelectrooxidationcomparedtothecatalystpreparedwithoutglucoseprotection.TheimprovedperformanceisattributedtothelargerelectrochemicalactivesurfaceareathusincreasedactivesitesonthePt/Celctrocatalystspreparedundertheprotectionofglucose.
简介:二新C-21steroidalglycosides,mucronatosidesM(1)和N(2),从白前科植物mucronata的茎被孤立,和一已知的复合stephanosideM(3)。根据化学证据和广泛的分光镜的方法,包括一个维、二维的NMR,二新混合物的结构作为12-O-tigloyl-20-O-N-methylanthraniloylsarcostin3-O--D-glucopyranosyl-(14)被识别-6-deoxy-3-O-methyl--D-allopyranosyl-(14)-(-D-cymaropyranosyl-(14)--D-cymaropyranoside(1),和12-O-cinnamoyl-20-O-nicotinoyl(20S)-pregn-6-ene-3(,5(,8,12,14(,17,20-heptanol3-O--D-glucopyranosyl-(14)-6-deoxy-3-O-methyl--D-allopyranosyl-(14)--D-cymaropy
简介:Twooxo-vanadium(IV)complexes,[VO(C2O4)(2,2′-bipy)(H2O)]·C2H5OH(1)andVO(C2O4)(phen)(H2O)(2),where2,2′-bipy=2,2′-bipyridyl,phen=1,10-phenanthroline,weresynthesizedaspotentialfunctionalmodelsofvanadiumhaloperoxidases(VHPOs)inmixedsolventofethanolandwateratroomtemperature.Thecomplexeswerecharacterizedbyelementalanalysis,infrared(IR),UV-VisandX-raycrystallography.Structuralanalysesshowedthatvanadiumatomwascoordinatedbyaterminaloxygen,oneoxygenatomfromcoordinatedwater,twooxygenatomsfromthecarboxylategroupofoxalicacid,andtwonitrogenatoms(N1andN2)from2,2′-bipy/phen.Centralvanadiumatomsincomplexes1and2werebothinadistorted-octahedralenvironment,andsomeintermolecularhydrogenbondinglinkageswerealsoobservedineachcomplex.BrominationreactionactivityofthetwocomplexeswasevaluatedwithphenolredasorganicsubstrateinthepresenceofH2O2,Br-andphosphatebuffer,indicatingthattheycanbeconsideredasapotentialfunctionalmodelofVHPO.Inaddition,thermalanalysiswasalsoperformedanddiscussedindetail.
简介:采用20种天然氨基酸的47个informationindices描述符、33个connectivityindices描述符和44个eigenvalue-basedindices描述符分别进行主成分分析,得出一种新的氨基酸描述符-SVICE.将其分别对三肽血管收缩素转化酶(ACE)、抗菌十八肽(AMP)、苦味活性二肽(BTT)序列表征后,建立结构与活性的SMR-MLR模型,并采用内外部双重验证的方法检验模型的稳定性.所建模型相关统计参量如下:复相关系数(Rcum2)、留一法(LOO)交互校验复相关系数(RCV2)和外部样本校验复相关系数(Qext2)分别为0.988,0.964,0.985;0.990,0.970和0.855;0.949,0.887,0.830.结果表明,运用SVICE描述符建立的MLR模型拟合、预测能力均较好,能较好解释肽类药物的活性与结构间的关系从而为新的强活性肽类药物的分子设计和改造提供了指导.
简介:FiveC3/C3fluoroquinolonedimerstetheredwithafusedheterocyclicringofs-triazolo[2,1-b][1,3,4]thiadiazolederivedfromantibacterialquinolonesweresynthesizedandcharacterized,andtheirinvitroantitumoractivityagainstL1210,CHOcelllineswasevaluatedviatherespectiveIC50values.